Background: This presentation will review pertinent studies on the effect of hormonal contraception on HIV acquisition, infectivity, and disease progression. Whether hormonal contraception increases susceptibility to HIV acquisition has been the subject of numerous studies in animals and humans. Results from 2 large, prospective studies that produced conflicting results—the Mombasa Cohort Study and the Hormonal Contraception-HIV (HC-HIV) Study—will be reviewed. Few well-executed studies have used an incident HIV outcome to assess the influence of hormonal contraception on HIV transmissibility. Most instead rely on cervico-vaginal viral shedding as a surrogate marker for infectivity. Data in this area suggest that hormonal contraception may increase shedding of cell-associated virus. Moreover, data from the Mombasa Cohort Study suggest that women using depot medroxyprogesterone acetate (DMPA) at the time of HIV acquisition had a higher viral set-point than women using non-hormonal methods and that they were more likely to acquire multiple viral variants, which in turn was associated with faster disease progression. A recent randomized trial of the intrauterine contraceptive device (IUD) versus hormonal contraception conducted in Zambia found an increased risk of disease progression (defined as either death or CD4 falling below 200 cells/mm³) in women allocated to hormonal contraception.

Conclusions: Data from these studies, as well as a large multi-country HIV treatment cohort, will be reviewed.